package com.neuedu.filter;

import com.alibaba.fastjson.JSON;
import com.neuedu.common.Result;
import com.neuedu.common.BaseContext;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@Slf4j
@WebFilter(filterName = "LoginCheckFilter", urlPatterns = "/*")
public class LoginCheckFilter implements Filter {

    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求{}", requestURI);

        //2.判断本次请求是否需要处理
        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employees/login",
                "/employees/logout",
                "/users/login",
                "/users/loginByCode",
                "/users/sendMsg",
                "/test/**",
                "/goods/list"
        };
        boolean check = check(urls, requestURI);
        if (check) {
            log.info("放行路径{}", requestURI);
            filterChain.doFilter(request, response);
            return;
        }
        //4-1.判断登录状态，如果已登录，则直接放行
        if (null != request.getSession().getAttribute("employee")) {
            log.info("用户已登录，用户id为{}", request.getSession().getAttribute("employee"));
            Long id = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(id);
            filterChain.doFilter(request, response);
            return;
        }
        //4-2.判断登录状态，如果已登录，则直接放行
        if (null != request.getSession().getAttribute("user")) {
            log.info("用户已登录，用户id为{}", request.getSession().getAttribute("user"));
            Long id = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(id);
            filterChain.doFilter(request, response);
            return;
        }
        //5.如果未登录则返回登录界面
        log.info("拦截到{}，用户未登录返回登录界面", requestURI);
        response.getWriter().write(JSON.toJSONString(Result.error("NOTLOGIN")));
    }

    /**
     * 路径匹配，判断本次请求是否需要放行
     *
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
